The UK-Canada-Hungary co-production for TV written by Julian Fellowes will be seen in more than 85 countries.

It is not easy sinking the Titanic in a landlocked country. That was just one challenge behind the new four-part event-TV production Titanic, directed by Jon Jones and written by Julian Fellowes.

The $17.4m (£11m) project has a truly international pedigree. It was originated in the UK with ITV and brought on partners in Hungary (where it shot) and Canada (where post was done).

ITV Global Entertainment has sold it to more than 85 countries around the world, including a rare US pre-sale with ABC. The first episode will be screened at MIPTV on April 1. The series launches worldwide in April timed to the 100th anniversary of the Titanic disaster.

Fellowes brings a touch of Gosford Park and Downton Abbey to his version of the Titanic story, by showing the many layers of social classes aboard the ship and the society that was heading for its own greater disaster, the First World War. He was recruited for the project by UK-based producer Nigel Stafford-Clark, who from the outset wanted to have the ship hitting the iceberg in all four episodes.

Fellowes says: “I knew this was my chance at the Titanic. When Nigel outlined the idea of taking the ship down every week, I knew I wanted to do it. You want to see how people behave in a disaster. I’ve always been fascinated and haunted by the Titanic… also as the whole of that world was on the edge of a cliff [in 1912] and didn’t know it.”

The interweaving characters (some fictional, some real) include a wealthy London couple with their suffragette daughter; an American silent movie star; an Irish couple in second class; America’s wealthy barons; young servants; families in steerage; and the men in charge of the ship. There are 82 main cast, led by Toby Jones, Linus Roache, Steven Waddington, Perdita Weeks, Sophie Winkleman, Stephen Campbell Moore, Celia Imrie and Geraldine Somerville, plus 2,500 extras.

‘I’ve always been fascinated and haunted by the Titanic’

Julian Fellowes

Stafford-Clark, who produced alongside Chris Thompson, notes this wealth of characters distinguishes this project from James Cameron’s box-office smash (which is being rereleased in cinemas in 3D in April). “With a TV show over four hours, we could tell a lot of stories. We could cover all the various elements of society. It’s something TV does really well. It does human stories,” he says.

Dublin was first eyed for the shoot but proved too expensive. Stafford-Clark was also keen to shoot in Belfast (where the Titanic was built). “It seemed right to do it there. But we needed a sizable grant. In the end they offered money but they couldn’t deliver it [quickly enough] and we couldn’t afford to wait.”

Project originator and executive producer Simon Vaughan of Lookout Point adds: “ITV being as generous as they were, it was still a big hill to climb to raise the $17.4m (£11m). We ended up in Hungary for a number of reasons both practical and financial.” Titanic also had support from the Broadcasting Authority of Ireland, the MEDIA Programme, The Bell Broadcast and New Media Fund and The Ontario Media Development Corporation.

Titanic is a co-production from ITV Studios with Stafford-Clark’s Deep Indigo and Vaughan’s Lookout Point in the UK, Shaw Media and Sienna Films in Canada (where post was done) and Mid Atlantic Films in Hungary.

The project shot for 10 weeks in Hungary, where several decks of the ship were built at Budapest’s Stern Studios, along with a large indoor water tank. The work was augmented by 470 VFX shots, supervised by Tom Turnbull.

Stafford-Clark, whose credits include Bleak House and The Passion, noted that post was another challenge: “The hardest thing to do with CGI is a metal ship. We didn’t know that when we started and neither did the effects houses.”

The cast and crew were pleased with their Hungarian experience — although Linus Roache has pointed out that shivering on the decks was a big acting job considering the Hungarian summer heat. Toby Jones added: “The scale of the building was extraordinary. It’s not what you associate with TV. There was an amazing team of Hungarians. They were extraordinary people to work with.”